June 2021

• name two pieces of equipment needed to prepare an onion sample for a microscope

  • scalpul
  • tweezers
• what is the function of the core focusing wheel

  to focus the image
• name structural differences of RBC and plant cell

  • plant cell has a permanent vacuole whereas RBC dosen't have one
  • • red blood cell has no nucleus or plant cell has a nucleus
  • • red blood cell has no cell wall or plant cell has a cell wall
  • • red blood cell is a biconcave disc or there are many different shapes of plant cell
  • • red blood cell contains haemoglobin or plant cells do not contain haemoglobin
  • • red blood cells do not contain chlorophyll or plant cells (may) contain chlorophyll
  • • red blood cell has no chloroplasts or plant cell has chloroplasts
  • • red blood cell has no (permanent) vacuole or plant cell has (permanent) vacuole
  • • red blood cells are (much) smaller than plant cells
• explain the financial impact on the UK economy of an increasing number of people who are obese (2 marks)

  costs the NHS / UK health service / Government / hospitals more money (because need to pay for) additional surgery / medication / hospital stay to treat stroke / diabetes or

  more time off work (if in hospital / unwell) (1) (so) employer / Government have to give financial support (1)
• give two uses of energy in respiration

  • movement
  • building larger molecules

  ignore growth
• (pondweed) - On day 10 the snail died. Explain why the death of the pond snail caused the concentration of CO2 to increase after day 10

  snail is being decayed / decomposed / broken down

  (by) decomposers / bacteria (in pond water / snail)

  (therefore) respiration (of decomposers / bacteria) releases CO2
• amylase is a polymer. what is the monomer

  amino acids
• explain in terms of lock and key theory how amylase breaks down startch

  starch / substrate binds to active site (of enzyme)

  (because) shape of active site and substrate are complementary

  (so) a chemical reaction occurs to produce smaller molecules
• whcih scientific term describes the movement of water up the roots and lost by the leaves

  Transpiration STREAM

  (ignore transpiration unqualified)
• why do less RBC cause tiredness

  • less oxygen in blood
  • so less aerobic respiration
  • so less energy provided for metabolic processes